% POSL Examples Using Sorted Unification Run in OO jDREW                2007-07-16
% Harold Boley, Benjamin L. Craig, Greg Sherman

% The RDF[S] type definitions are visualized in:
% http://www.jdrew.org/oojdrew/6905-slides.pdf (slide 31)
% and their source can be loaded from:
% http://www.jdrew.org/oojdrew/carTypes.rdf


% Positional Fact

% Fact: Budget has available all objects that are passenger vehicles.
available(Budget,?:PassengerVehicle).

% Query (rule): Does Budget have available an object that is a passenger vehicle?
an(?X) :- available(Budget,?X:PassengerVehicle).

% Query (rule): Does Budget have available an object that is a minivan?
an(?X) :- available(Budget,?X:MiniVan).

% Query (rule): Does Budget have available an object that is a van?
an(?X) :- available(Budget,?X:Van).


% Positional Fact and Rule

% Rule: Budget rents an object that is a passenger vehicle to a ?Y if
%       ?Y is licensed for passenger vehicles.

rents(Budget,?:PassengerVehicle,?Y) :-
  licensed(?Y,?:PassengerVehicle).

% Fact: John is licensed for passenger vehicles.
licensed(John,?:PassengerVehicle).

% Query (rule): Does Budget rent an object that is a passenger vehicle to someone?
anp(?X,?P) :- rents(Budget,?X:PassengerVehicle,?P).

% Query (rule): Does Budget rent an object that is a minivan to someone?
anp(?X,?P) :- rents(Budget,?X:MiniVan,?P).

% Query (rule): Does Budget rent an object that is a van to someone?
anp(?X,?P) :- rents(Budget,?X:Van,?P).


% Slotted Fact and Rule

% Rule: Budget rents an object that is a passenger vehicle to a ?Y if
%       ?Y is licensed for passenger vehicles.

rents(company->Budget;rental->?:PassengerVehicle;driver->?Y) :-
  licensed(person->?Y;device->?:PassengerVehicle).

% Fact: John is licensed for passenger vehicles.
licensed(person->John;device->?:PassengerVehicle).

% Query (rule): Does Budget rent an object that is a passenger vehicle to someone?
ans(?X,?P) :- rents(company->Budget;rental->?X:PassengerVehicle;driver->?P).

% Query (rule): Does Budget rent an object that is a minivan to someone?
ans(?X,?P) :- rents(company->Budget;rental->?X:MiniVan;driver->?P).

% Query (rule): Does Budget rent an object that is a van to someone?
ans(?X,?P) :- rents(company->Budget;rental->?X:Van;driver->?P).